JPH0244487A - 7b character reading system for optical character reader - Google Patents

Abstract

PURPOSE:To heighten a recognition rate and to perform fast reading by extracting a character linear component forming a 7B character corresponding to each character position from the data of a linear component provided for the discrimination of the character position, and performing the recognition of a corresponding 7B character. CONSTITUTION:A linear component detecting means 101 detects the linear component by fetching image data from paper on which an embossed 7B character is transferred, and a character position discrimination means 103 discriminates the character position from the distributed state of the central point of the linear component. A character linear component extraction means 105 extracts the character linear component which forms the 7B character from the data of the linear component corresponding to each character position, and a character recognition means 107 performs the recognition of the corresponding 7B character from an extracted character linear component. Since the recognition of a character is performed directly from the data of the linear component in such way, the character recognition ratio can be heightened and the fast reading can be realized.

Description

[Detailed Description of the Invention] [Summary] Regarding the 7B character reading method of an optical character reading device that imprints, for example, embossed 7B characters on paper or other material and reads the 7B characters transferred thereto, the recognition rate of 7B characters has been evaluated. In order to improve the image quality and enable high-speed reading, we have developed a linear component detection means that captures image data of a predetermined area including 7B characters and detects the linear component, and a linear component detection means that detects the linear component from the distribution state of the center point of this linear component. In an optical character reading device that is equipped with a character position determination means for determining the character position and performs character recognition corresponding to each character position, a Te7B
A character straight line component extraction means for extracting character straight line components forming a character, and ii! of the corresponding 7B character from the extracted character straight line components. i! character recognition means for performing recognition.

[Industrial application field]

The present invention is a method of imprinting 7B characters embossed (characters are formed on convex parts by deforming the thin plate) on a card such as a cash card onto a form (pressing pressure-sensitive paper or applying ink with an ink roller). It relates to an optical character reading device that reads 7B characters transferred thereto.

In particular, the present invention relates to a 7B character reading method that increases the recognition rate of transcribed 7B characters and enables high-speed reading.

[Conventional technology]

In conventional optical character reading devices, imprinted 7B characters are read in the same manner as printed characters are read. That is, as shown in FIG. 5, the distribution states 503 and 505 of the number of pixels in the vertical and horizontal directions are obtained from the character image 501, and the break in the character is detected from the position where the distribution of the number of pixels is the minimum, and the discrimination is performed. The system cut out a character pattern corresponding to the specified character position and recognized the character by comparing it with a standard pattern.

However, when embossed characters are imprinted, dirt 511 tends to adhere to the periphery of the characters, and the characters tend to be "chipped" or "collapsed", so the minimum position of the pixel count distribution is at the cut-off of the characters. They may not match. In this case, compared to printed characters, character position determination becomes inaccurate and the character recognition rate decreases.

In order to solve this problem, since the 7B character is formed by a combination of vertical and horizontal straight lines,
A character reading device that increases the character recognition rate by detecting linear components in each direction, determining the character position from the position of the linear component (distribution state of the center point), and recognizing the characters in the same manner. Filed by the same applicant (Patent Application 1986-
83849).

FIG. 6 is a diagram illustrating a characteristic part of this prior application method (character position determination for cutting out a character pattern from image data).

FIG. 6(a) shows a character image read by a scanner. FIGS. 6(b) and 6(d) show a state in which straight line components having a predetermined length or more are detected among the straight lines forming the 7B character, and are displayed separately in the vertical and horizontal directions. 6th
Figures (C) and (e) show the distribution of the center points of each straight line component.

The center position of the character is detected from the maximum position of the distribution of each center point, and the breaks between characters and lines are determined.
Cut out one character pattern according to the character position,
Character recognition is performed.

This linear component detection process in each direction makes it possible to detect character positions that are unaffected by stains other than characters that occur during imprinting, missing or crushed characters, and improves character recognition rates. .

[Problem to be solved by the invention]

In this way, the first application method extracts character position information (distribution state of the center point of the straight line component) from the character image by detecting its linear component, determines the character position, and makes it possible to reliably cut out character patterns. However, the recognition process in which characters are recognized by cutting them out and comparing them with standard patterns was the same as the conventional method.

The present invention eliminates the need for character pattern cutting processing, allows character recognition to be performed directly from linear component data used to determine character positions, and provides optical characters that have a high character recognition rate and enable high-speed reading. The purpose of this invention is to provide a method for reading 7B characters using a reading device.

[Means to solve the problem]

FIG. 1 is a block diagram of the principle of the present invention.

In the figure, a straight line component detecting means 101 takes in image data of a predetermined area including the transferred characters obtained from the embossed 7B characters transferred and detects the straight line components.

The character position determination means 103 determines the character position from the distribution state of the center points of this straight line component.

The character straight line component extraction means 105 extracts character straight line components forming a 7B character according to each character position from the straight line component data used for character position determination.

The character recognition means 107 recognizes the corresponding 7B character from the extracted character line component.

[For production]

The present invention detects a straight line component from image data and determines the character position from the distribution state of its center point.The present invention uses a configuration that detects a straight line component from image data and determines the character position from the distribution state of the center point. By extracting the components, it is possible to recognize the corresponding 7B characters.

In other words, since the 7B character is formed of predetermined linear components, the linear component data used to determine the character position has sufficient information to identify the 7B character, and that information can be analyzed. The character recognition means 107 can recognize the 7B character from data of character straight line components extracted for each character position.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 2 is a block diagram showing the configuration of an embodiment of the present invention.

In the figure, corresponding image data is obtained from a scanner unit 201 that scans a predetermined area including the 7B characters for a form on which the 7B characters embossed on the card are imprinted. The image data (■) of a character string having a plurality of 7B characters is stored in the image memory 203.

The straight line component detection unit 205 takes in the image data (■) from the image memory 203 and temporarily stores the detected straight line component (2) in the straight line component table 207. This straight line component (2) is sent to the character position determining section 209, where the character position is determined using the first application method.

The character position ■ and the straight line component ■ determined here are taken into the character straight line component extraction section 211, and the character straight line component ■ forming each 7B character is extracted according to the character position and sent to the character recognition section 213. Ru.

The character recognition unit 213 recognizes each 7B character based on the character linear component (2), and outputs a recognition result (2).

FIG. 3 is a diagram showing an example of a 7B character.

In the figure, the 7B character is 1. It is formed from straight line components corresponding to a predetermined length 28 determined from its width, a predetermined length j2h+ determined from its height, and a length ehl which is about 2 of the length j2h+.

Note that "b", "good", and "9" shown here have straight line components corresponding to all lengths fiw and ghIs lhz, but "0", "1", and "]" have linear components corresponding to length 1. ．． ,,
, there is only a linear component corresponding to I, and "2", "
Horizontal, “5” and “8” are length! 1,! , , only the linear components corresponding to □.

In this way, the 7B character has linear components corresponding to each length, and the linear component detection section 205 shown in FIG. 2 detects the linear components corresponding to each length.

Figure 4 shows 7
It is a figure explaining the process of recognizing a B character.

The symbols in each figure are the symbols for each part shown in Figure 2 (■, ■,
■).

The operation of this embodiment will be described below with reference to FIGS. 2 to 4.

The straight line component detecting unit 205 detects a horizontal straight line component ■8 and vertical straight line components ■2 and ■3 from the image data ■. In other words, the straight line component ■1 is the width of a 7B character! It is a straight line part with a length corresponding to 8, and the straight line component ■2 is its height e
It is a straight line portion with a length corresponding to hl, and the straight line component 3 is a straight line portion with a length corresponding to 26□, which is about 2 of the height ffhl.

The character position determination unit 209 calculates the local maximum values from the center point distribution states ■, @, and ■ of each linear component, extracts the one that matches the character spacing from the center point distribution state ■, and calculates its horizontal position. The character position in the horizontal direction is determined by determining the position of the character in the horizontal direction, and the position in the vertical direction is similarly determined from the distribution state of the center point @, ■ to determine the character position in the vertical direction.

Note that the above configuration and operation are equivalent to the prior application system.

In accordance with the character position (range of each 7B character) ■ determined in this way, the character straight line component extraction unit 211 extracts the character straight line component ■ forming the 7B character from the straight line components in each range. .

The character recognition unit 213 refers to a dictionary (table) showing the relationship between the character linear component (2) and the 7B character corresponding to the character, and recognizes the 7B character corresponding to the combination of each linear component. Although the character formed by the combination of each linear component is not the original 7B character itself, it can be identified by comparing it with a standard pattern.

In this way, the 7B character formed thereby can be recognized using the data of the straight line component (2) used for the determination without cutting out the character image again according to the determined character position.

〔Effect of the invention〕

As described above, according to the present invention, in the recognition of 7B characters transferred to paper or other materials, in order to directly recognize the 7B characters by using the linear component data used to determine the character position, In addition to increasing the character recognition rate, it also becomes possible to read the characters at high speed, which is extremely useful in practice.

[Brief explanation of the drawing]

Figure 1 is a block diagram of the principle of the present invention, Figure 2 is a block diagram showing the configuration of an embodiment of the present invention, and Figure 3 is a block diagram of the principle of the present invention.
The figure shows an example of a 7B character.
Figure 5 is a diagram explaining the process of character recognition, Figure 5 is a diagram explaining character reading using the conventional method, and Figure 6 is a diagram explaining the characteristics of the prior application method (character position determination to cut out character patterns from image data). This is a diagram. In the figure, 101 is a straight line component detection means, is a character position discrimination means, is a character straight line component extraction means, is a character recognition means, is a scanner section, is an image memory, is a straight line component detection section, is a straight line component table, is a character position is the discrimination section, is the character straight line component extraction section, and is the character recognition section. Wooden G Mere bu Aro, 7th Figure 1 Figure 7th Tacori 9 o) - A row Figure 2 Dag2 wo B8 Kaku 1 Ka Figure 5

Claims (1)

[Claims] (1) Straight line component detection means (101
) and a character position determining means (103) for determining character positions from the distribution state of center points of the linear components, and performs character recognition corresponding to each character position. From the linear component data used to determine
A character straight line component extracting means (105) for extracting a character straight line component forming a 7B character according to each character position, and a character recognition means (107) for recognizing a corresponding 7B character from the extracted character straight line component. A 7B character reading method of an optical character reading device characterized by comprising: